Journal of King Saud University, Engineering Sciences最新文献

{"title":"A simple analytical method for accurate prediction of the leakage reactance and leakage energy in high-voltage transformers","authors":"Kamran Dawood,&nbsp;Güven Kömürgöz","doi":"10.1016/j.jksues.2022.06.002","DOIUrl":"10.1016/j.jksues.2022.06.002","url":null,"abstract":"<div><div>Transformers are one of the most crucial pieces of equipment for the distribution and transmission of electric power. A high-voltage transformer plays a vital role to reduce power losses during the transmission of electricity. Leakage reactance plays a vital role in the working and stability of the transformer. The accurate prediction of the leakage reactance is a great asset to the transformer designers during the manufacturing stage to attain the dynamically optimum design of the transformer. In the literature, mostly given analytical techniques for leakage reactance calculations are applied to the transformers with the symmetric axial heights of the low-voltage, and high-voltage windings. Therefore, a proper analytical prediction for the leakage reactance in the transformer with asymmetric axial heights is needed to implement an optimized design. This paper proposes a new advanced method for an accurate calculation of the leakage reactance and leakage energies in different parts of the transformer with symmetrical and asymmetrical axial heights of the windings. Moreover, the finite element method and three different analytical methods are also compared with a new analytical technique for 5 real cases. For 2 cases, the proposed method’s results are also verified by experimental tests. The method’s accuracy in predicting the stored energy and leakage reactance of the high-voltage transformer is found to be more accurate and much simpler than the other analytical methods.</div></div>","PeriodicalId":35558,"journal":{"name":"Journal of King Saud University, Engineering Sciences","volume":"36 8","pages":"Pages 572-580"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80522496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Energy performance evaluation of variable-speed milk refrigerator using propane (R290)","authors":"Shailendra Kasera ,&nbsp;Rajlakshmi Nayak ,&nbsp;Shishir Chandra Bhaduri","doi":"10.1016/j.jksues.2022.05.006","DOIUrl":"10.1016/j.jksues.2022.05.006","url":null,"abstract":"<div><div>Hydrofluorocarbons (HFCs) such as R134a, R410A, and R407C may not be the long-term solution for the HVAC &amp; R industry due to their higher potential for global warming. People’s interest is now shifting toward alternate refrigerants like hydrocarbons (HCs). In this research paper, an experimental energy performance evaluation of a variable-speed milk refrigerator was conducted using propane (R290). R290 has good environmental and thermodynamic properties, and it is known as a fourth-generation refrigerant. Various performance parameters, such as Cooling Capacity, COP, and Compressor Energy Consumption, are analyzed using different speeds of DC compressor. The DC compressor has four different types of fixed speed along with one variable speed operation. The results achieved from the performance tests are presented and discussed.</div></div>","PeriodicalId":35558,"journal":{"name":"Journal of King Saud University, Engineering Sciences","volume":"36 8","pages":"Pages 632-637"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73186305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Removal of 2,6-dichlorophenol by adsorption with activated polypropylene nanofiber","authors":"Duduku Krishnaiah ,&nbsp;Arswitaa Baskaran ,&nbsp;S.M. Anisuzzaman ,&nbsp;Reddy Prasad D.M.","doi":"10.1016/j.jksues.2021.10.007","DOIUrl":"10.1016/j.jksues.2021.10.007","url":null,"abstract":"<div><div>2,6-Dichlorophenol is an organochloride of phenol, and it is considered one of the emerging pollutants in wastewater due to its extreme corrosive nature and toxicity even at low concentrations. Melt-blown activated polypropylene (PP) nanofiber is a polymeric adsorbent and it is used to investigate the removal of 2,6-dichlorophenol. The high surface-to-volume ratio, high porosity, low surface energy, low density, and excellent mechanical characteristics of melt-blown PP nanofiber make it a suitable adsorbent. On the removal efficiency of 2,6-dichlorphenol, the influence of the initial concentration of 2,6-dichlorphenol, the weight of PP nanofiber utilized, temperature, and pH of the solution were examined. The Langmuir model, with a maximum adsorption capacity of 44.44 mg/g, was found to be the best match for the adsorption isotherm. Scanning Electron Microscopy (SEM) and Fourier-Transform Infrared Spectroscopy were used to examine melt-blown PP nanofiber before and after adsorption (FTIR). Through SEM images, it was proven that the average diameter of PP nanofiber after adsorption had increased up to 7.93 <span><math><mrow><mi>μ</mi><mi>m</mi><mo>.</mo></mrow></math></span> Furthermore, the existence of phenolic chemicals on the surface of PP nanofiber is confirmed by FTIR analysis spectra. The pseudo-first-order model matched the kinetic data nicely.</div></div>","PeriodicalId":35558,"journal":{"name":"Journal of King Saud University, Engineering Sciences","volume":"36 8","pages":"Pages 677-683"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85591952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of corrugated side-walls on plane turbulent wall jets in narrow channels","authors":"Shazy Shabayek,&nbsp;Ehab Fattouh,&nbsp;Samir Ead","doi":"10.1016/j.jksues.2022.09.002","DOIUrl":"10.1016/j.jksues.2022.09.002","url":null,"abstract":"<div><div>An experimental study is presented to investigate the effect of corrugated sidewalls on submerged wall jets in narrow channels. Experiments were performed in a flume 0.3 m wide, 0.5 m deep, and 13.5 m long. Jets issued under the gate with a fixed thickness of 2.5 cm and the tailwater depth was adjusted to 37.5 cm, giving a fixed tailwater depth ratio y_t/b_o = 15. Experiments were conducted for five slot Froude numbers 2, 3, 4. 5, and 6. The Reynolds number ranged between 24712 and 74136. Three sets of experiments of five runs each, were performed. In Set A, the experiments were performed with smooth sidewalls whereas in Sets B and C, two arrangements of corrugated sidewalls (with gaps and with no gaps) were used, respectively. Velocity profiles along the centerline of the flume, water surface profile and the eddy length were measured for each experiment. It was found that the corrugations with gaps caused the largest decay in the maximum velocity; however, the effect of the presence of the sidewall corrugations on the velocity decay diminishes with the Froude number. Furthermore, the corrugated sidewalls with no gaps were observed to induce more flow entrainment and therefore cause a steep increase in the jet discharge and momentum flux near the slot. However, the corrugated sidewalls with gaps induced more mixing and diffusion, farther downstream from the slot, and caused a faster decay in the jet discharge and momentum. The use of corrugated sidewalls is introduced in this study as an alternative technique, to corrugated beds, to be used for energy dissipation in narrow channels. The sidewall corrugations are easier to maintain as less debris/sediments are trapped in between the corrugations. In addition, if channel maintenance is required, the movement of the maintenance facilities on a smooth bed would be much easier than that on a corrugated bed. Moreover, the sidewall corrugations will not be damaged during the maintenance process.</div></div>","PeriodicalId":35558,"journal":{"name":"Journal of King Saud University, Engineering Sciences","volume":"36 8","pages":"Pages 652-661"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89493943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring the Barriers to Implementing the Integrated Project Delivery Method","authors":"Rudhab S. Buk'hail,&nbsp;Ruqaya S. Al-Sabah","doi":"10.1016/j.jksues.2022.04.003","DOIUrl":"10.1016/j.jksues.2022.04.003","url":null,"abstract":"<div><div>The willingness of Kuwait’s construction industry to implement the new and emerging delivery system, the Integrated Project Delivery method (IPD), was explored in this research. As general conclusions to the barriers to IPD are already established by existing literature, this research aims to identify the specific barriers to IPD by evaluating the willingness of non-IPD teams to implement the principles of IPD. Data was collected from members engaged in multiple construction projects located in Kuwait. Statistical analyses were performed on the collected data to examine differences and similarities in their responses. A Delay Index variable revealed that ongoing Design-Bid-Build (DBB) projects are suffering a delay that amounts to half their original construction duration and that is almost double the delay incurred on Design-Build (DB) projects, which suffered a lesser delay. The data was further analyzed based on the respondents’ project delivery system, project sector, years of experience, and project party. The results indicated that the majority of the respondents working in Kuwait were willing to implement most of IPD’s principles. Astonishingly, respondents working on DBB projects were more willing to implement the principles of IPD than those working on DB projects. The respondents from both the public and private sectors were equally willing. The main contractors were found to be less willing to implement IPD than all the other project parties. Moreover, the most prominent barriers prohibiting most respondents from implementing IPD was their unwillingness to sign a contract that includes liability waivers and one that includes IPD’s organizational hierarchical structure. The findings of this research contribute to the current body of knowledge by exploring the construction industry’s willingness to implement IPD and by simultaneously identifying the specific barriers to its implementation, as well as identifying where these barriers lie.  These findings may be used as evidence by owners or industry pioneers in promoting the implementation of IPD in their respective organizations.</div></div>","PeriodicalId":35558,"journal":{"name":"Journal of King Saud University, Engineering Sciences","volume":"36 8","pages":"Pages 543-551"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76675460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A simple control strategy and dynamic energy management for the operation of combined grid-connected and standalone solar photovoltaic applications","authors":"Rakesh Namani ,&nbsp;Senthilkumar Subramaniam ,&nbsp;SarojiniMary Samikannu ,&nbsp;Madhusudanan Gurusamy","doi":"10.1016/j.jksues.2021.12.009","DOIUrl":"10.1016/j.jksues.2021.12.009","url":null,"abstract":"<div><div>There is an increased focus on energy savings in low-voltage DC (LVDC) loads for home appliances. The use of LVDC for the local distribution system enables easier integration with renewable sources. This work presents the control and management of power flow to DC loads in grid-tied photovoltaic (GPV) systems. This system provides bi-directional flow of power from the DC load to the AC grid, using a pulse width modulation (PWM) technique, employing a voltage source inverter between the DC nano grid and the AC main grid. The bidirectional converter controls the active power transferred in both directions while operating at unity power factor (UPF). The modified three-level hysteresis current controller and the voltage controller are designed as the inner loop and the outer loop, respectively, to control the bi-directional power flow. The corresponding grid voltages and currents are used to generate the reference currents. The proposed system has been validated through MATLAB/Simulink simulations and experimentation on a prototype system developed in the laboratory controlled by the dSPACE 1103 real-time digital controller board. The results show that a regulated DC voltage is obtained for dynamic changes of source and load like in a real-time environment. The control strategy with its validation shows the efficacy of the proposed system.</div></div>","PeriodicalId":35558,"journal":{"name":"Journal of King Saud University, Engineering Sciences","volume":"36 8","pages":"Pages 591-599"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73653669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental investigation of mechanical sustainability and acoustic performance of fly ash cenosphere/epoxy polymer composites","authors":"Sriharsha Hegde,&nbsp;N.H. Padmaraj,&nbsp;V. Siddesh,&nbsp;T.S. Sunaya,&nbsp;K. Adithya Kini,&nbsp;Vishal K. Sanil","doi":"10.1016/j.jksues.2021.11.002","DOIUrl":"10.1016/j.jksues.2021.11.002","url":null,"abstract":"<div><div>Hollow spherical fly ash cenosphere is a by-product of the coal firing process in thermal power plants and nowadays has become a substitute for the other organic fillers in the composite industry. The present study investigates the mechanical and acoustic performance of cenosphere/epoxy-based polymer composites. Void content, Shore Hardness, Tensile, Flexural, Impact, and Acoustic studies were conducted on epoxy specimens containing 0, 3, 5, and 7% of cenosphere by weight. Surface morphology and failure pattern of the tensile failure samples were investigated using the scanning electron microscope technique. Incorporation of cenosphere into epoxy reduced the void content from 4.27 to 2.54 % and increased the Shore hardness from 80.8 ± 1.44 to 85.8 ± 1.78 when the filler content was increased from 3 to 5%. Impact strength, Tensile and Flexural modulus showed an incremental trend with the increase in the weight percentage of the cenosphere. Examination of the tensile failure surface showed the presence of twist hackles and better interlocking of cenosphere with epoxy matrix. The density of the specimens played vital role in sound absorption characteristics. The addition of the cenosphere in epoxy deteriorates the sound absorption behaviour of the material as compared to neat epoxy.</div></div>","PeriodicalId":35558,"journal":{"name":"Journal of King Saud University, Engineering Sciences","volume":"36 8","pages":"Pages 646-651"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90883542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A study of catalyst operating regimes using alumina-supported catalytic plates for CO oxidation in a microreactor","authors":"Rehana Kousar ,&nbsp;Sang Hoon Kim ,&nbsp;Ji Young Byun","doi":"10.1016/j.jksues.2021.09.003","DOIUrl":"10.1016/j.jksues.2021.09.003","url":null,"abstract":"<div><div>The performance of a microreactor loaded with Pd/Alumina catalytic plates was tested for CO oxidation as a model reaction. A microreactor with a feasible joining method was designed for catalytic processes. Further, this study aimed to investigate the correlation of metal active phase and support thickness towards catalytic activity. Experiments on CO oxidation showed that the catalyst activity of the active material can be improved by controlling both the catalyst oxidation state and support thickness. Pd in oxide form (PdO) showed better catalytic activity as compared with that of the metallic Pd. Furthermore, given the same amount of deposited Pd, the catalytic activity was enhanced by decreasing the catalyst support thickness, which is due to an increase in the surface concentration of the active metal as a result of its shallow dispersion. The results showed that increasing film thickness within a certain range (∼30 µm) could significantly improve the catalyst activity.</div></div>","PeriodicalId":35558,"journal":{"name":"Journal of King Saud University, Engineering Sciences","volume":"36 8","pages":"Pages 709-716"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80285652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A new approach to predict the formation pressure using multiple regression analysis: Case study from the Sukharev oil field reservoir – Russia","authors":"Inna N. Ponomareva ,&nbsp;Dmitriy A. Martyushev ,&nbsp;Suresh Kumar Govindarajan","doi":"10.1016/j.jksues.2022.03.005","DOIUrl":"10.1016/j.jksues.2022.03.005","url":null,"abstract":"<div><div>Formation pressure is an important indicator of field production potential. Currently, the common practice to estimate reservoir pressure is the hydrodynamic exploration test. This method requires shutting down the well, often for a long time. Such long shutdowns lead to less production from the reservoir and worsen the economics of the field. Here, we present the method for determining the pressure without shutting down the well by using statistical methods for such tasks. In this article, we describe the method of finding the formation pressure by using multidimensional multivariate analysis of the actual reservoir data from the Sukharev field. To build the model, several operational, geological, and reservoir properties at various stages of the field pressure were combined into a model to predict reservoir pressure. Results showed that with this simple statistical method, formation pressure varies in two distinctive stages. In the first stage, the formation pressure is influenced by the reservoir petrophysical parameters, whereas in the second stage, operational parameters were more prominent. Finally, three separate formations in the Sukharev field were examined to predict reservoir pressure, and the results were in very good agreement with the actual measured data. This confirmed that the method was practical and capable of predicting reservoir pressure at any time of the well's lifetime.</div></div>","PeriodicalId":35558,"journal":{"name":"Journal of King Saud University, Engineering Sciences","volume":"36 8","pages":"Pages 694-700"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90089988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modelling of an Integrated Plasma Gasification Combined Cycle power plant using Aspen Plus","authors":"Néstor D. Montiel-Bohórquez,&nbsp;Andrés F. Agudelo,&nbsp;Juan F. Pérez","doi":"10.1016/j.jksues.2022.06.004","DOIUrl":"10.1016/j.jksues.2022.06.004","url":null,"abstract":"<div><div>The development of a steady-state model of an Integrated Plasma Gasification Combined Cycle (IPGCC) power plant is presented here. The model includes the plasma gasifier, syngas conditioning units, and the power generation unit. Furthermore, the model of each component implemented in Aspen Plus is described in detail (thermodynamic method, chemical reactions, and operative conditions). The proposed model was validated by comparing the plasma gasification results with experimental and numerical data from the literature; the relative error was 6.23% and 5.24%, respectively. The model was then used to perform a two-part sensitivity analysis. In the first part, simulations with municipal solid waste (MSW) with a moisture content varying from 20% to 60% were performed. The moisture content increment reduced the torch-specific power consumption by 53%. However, because of the increasing specific fuel consumption, the thermal efficiency of the IPGCC power plant also decreased by 28% as the MSW moisture content increased from 20% to 60%. In the second part, it was determined that the IPGCC power plant reached the best performance (32.5%) when a high plasma temperature (5000 °C) and a low gasification temperature (2000 °C) were used. At these highest efficiency conditions, the 1000 t/day IPGGC power plant’s net power generation was 62 MWe.</div></div>","PeriodicalId":35558,"journal":{"name":"Journal of King Saud University, Engineering Sciences","volume":"36 8","pages":"Pages 620-631"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77237817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}